kx1 - receive high current drain only with dummy load

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kx1 - receive high current drain only with dummy load

Bob Tomas
Hello,

I have had a KX-1 for about a year now and it seems to be working OK.  

However, I was testing the transmitter and connected a 50 ohm dummy load.  During the course of my transmitter tests, I noticed that the dummy load got warm when I wasn't transmitting.  I measured the KX-1 input current and found that the I was drawing about 0.300 A with the dummy load attached while receiving.  With a random wire attached in place of the dummy load, the current draw dropped to 0.040A, which is close to the tolerances specified in the manual.  Does this indicate there is a problem with the radio?


Bob

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Re: kx1 - receive high current drain only with dummy load

Don Wilhelm-4
Bob,

Yes you have a problem.  If C44 is shorted, it would cause exactly the
symptoms you report.
Change C44 before you do anything else.  If you connect an antenna with
a low DC resistance path to ground, it will draw a lot more current than
the 300 ma - in fact it can draw enough current to either trip your
power supply or to vaporize one of the PC board voltage traces in your
KX1.  Right now, it is unlikely that there is anything else wrong with
your KX1, just change the capacitor.

73,
Don W3FPR

Bob Tomas wrote:

> Hello,
>
> I have had a KX-1 for about a year now and it seems to be working OK.  
>
> However, I was testing the transmitter and connected a 50 ohm dummy
> load.  During the course of my transmitter tests, I noticed that the
> dummy load got warm when I wasn't transmitting.  I measured the KX-1
> input current and found that the I was drawing about 0.300 A with the
> dummy load attached while receiving.  With a random wire attached in
> place of the dummy load, the current draw dropped to 0.040A, which is
> close to the tolerances specified in the manual.  Does this indicate
> there is a problem with the radio?
>
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